From 4a568a14077bd4cf03878ee9e2d8fb7e79ff7641 Mon Sep 17 00:00:00 2001
From: Nick Wellnhofer <wellnhofer@aevum.de>
Date: Wed, 2 Nov 2022 10:53:24 +0100
Subject: [PATCH 3/3] schemas: Fix infinite loop in
 xmlSchemaCheckElemSubstGroup

Types like xmlSchemaTypeAnyTypeDef have a base type pointing to itself,
resulting in an infinite loop.

Fixes #430.
---
 xmlschemas.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/xmlschemas.c b/xmlschemas.c
index 2da962b..a62db2d 100644
--- a/xmlschemas.c
+++ b/xmlschemas.c
@@ -19957,7 +19957,8 @@ xmlSchemaCheckElemSubstGroup(xmlSchemaParserCtxtPtr ctxt,
 	    /*
 	    * The set of all {derivation method}s involved in the derivation
 	    */
-	    while ((type != NULL) && (type != headType)) {
+	    while ((type != NULL) && (type != headType) &&
+                   (type != type->baseType)) {
 		if ((WXS_IS_EXTENSION(type)) &&
 		    ((methSet & XML_SCHEMAS_TYPE_BLOCK_RESTRICTION) == 0))
 		    methSet |= XML_SCHEMAS_TYPE_BLOCK_EXTENSION;
-- 
2.27.0